 /*******************************************************************************
  * Copyright (c) 2000, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui;

 import org.eclipse.jface.viewers.ISelection;

 /**
  * Interface for listening to selection changes.
  * <p>
  * This interface may be implemented by clients.
  * </p>
  *
  * @see ISelectionService#addSelectionListener(ISelectionListener)
  * @see ISelectionService#addSelectionListener(String, ISelectionListener)
  * @see org.eclipse.ui.INullSelectionListener
  */
 public interface ISelectionListener {
     /**
      * Notifies this listener that the selection has changed.
      * <p>
      * This method is called when the selection changes from one to a
      * <code>non-null</code> value, but not when the selection changes to
      * <code>null</code>. If there is a requirement to be notified in the latter
      * scenario, implement <code>INullSelectionListener</code>. The event will
      * be posted through this method.
      * </p>
      *
      * @param part the workbench part containing the selection
      * @param selection the current selection. This may be <code>null</code>
      * if <code>INullSelectionListener</code> is implemented.
      */
     public void selectionChanged(IWorkbenchPart part, ISelection selection);
 }

